Carcinoma of the anus treated with primary radiation therapy and chemotherapy.

Between 1983 to 1989, 24 patients with previously untreated carcinoma of the anal canal (less than 3 centimeters in five patients and more than 3 centimeters in 19 patients) were entered in a prospective nonrandomized protocol of primary radiotherapy (4,050-4,500 cGy days one to 28) and chemotherapy (10 milligrams per meter squared of mitomycin C, on day two and 1,000 milligrams of 5-fluorouracil per molar squared for days two to five and 28 to 32). Therapy was discontinued for two patients because of severe (grade 4) skin reactions. The remaining patients tolerated the regimen well, with the exception of two patients who had grade 3 hematologic toxicity and three patients with grade 3 to 4 complications of the gastrointestinal tract. All of the patients who completed the regimen had a complete clinical and pathologic response when restaged six weeks after completion of therapy. All patients with lesions of less than 3 centimeters and 13 of 19 patients with lesions greater than 3 centimeters have remained free of disease (median follow-up period of 41 months; median survival rate of 36 months). Before 1983, 19 patients underwent abdominal perineal resection as primary treatment for carcinoma of the anus. Only six of seven patients with lesions less than 3 centimeters and zero of the 12 patients with lesions equal or greater than 3 centimeters have remained alive and free of disease. Eighteen of 24 patients treated with chemotherapy and radiotherapy only have remained free of disease and have preserved anal function. These results are superior to those reported with primary surgical treatment and primary radiotherapy only.